Railway-traffic-controlling apparatus



mm. 4 i924,

513.95? 0. R. BEALL ET AL RAILWAY TRAFFIC CONTROLLING APPARATUS Filed Nov. 29. 1922 C-.R. Ben/l, and R-M.G,'ilson,

IN VENTORS I Patented Nov. 4, 1924.

UNITED STATES PA TEN T ()F F CHARLES R. BEALL, 01F LSWISSWALE, AND ROBERT M. GIBSON, .01? EITTSBUER-GH, PENN- SYLVANIA, ASSEKGN'O'BSEO THE ,UNZBON SWITCH. 6r, SIGNAL COIMPANY, 0F SWISS- VAIJE, PENNSYLVANIA, AfiGQRPORATIDN OF EENNSYLVANIA.

BAILWAY-.TRAFFIC-GONTROLLINZG APPARATUS,

Application filed November 29, 1822.

To aZZ whom it may concern:

Be it known that we, CHARLES R. BEALL and ROBERT M. 'GILsoN, citizens of the United States, residing at Swissvale and Pittsburgh, respectively, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improvements in Railway Tralilc-Controlling Apparatus, of which the following is a specification.

Our invention relates to railway traliic controlling apparatus, and particularly to apparatus of the type wherein railway signals or other traiiic governing devices are controlled by track circuits. 'Uur invention is particularly well adapted for, though not necessarily limited to, railways oft-he electric propulsion type.

We will describe one form and arrangement of railway trafiic controlling apparatus embodying our invention, and will then point out the novel features thereof in claims.

The accompanying drawing is a view, partly diagrammatic, showing one form of railway trafiic controlling apparatus embodying our invention.

Referring to'the drawing,the reference character 2 designates thetrack rails of a railway over which traliic normally moves in the direction indicated by the arrow. These rails are divided by insulated joints 1 into a plurality of track sections of which only one section AB is shown in the drawing. Propulsion current is supplied by a generator G one terminal of which isconnected with a trolley wire or third ra'il'E and the other terminal to the track rails in the usual and well known manner through an impedance E28 normally balanced so as to oller low impedance to the propulsion current. This propulsion current is conducted past the insulated oints 1 by means of normally balanced impedance bonds 29'which oli'er low impedance to the propulsion current which flows through both rails in multiple, but a high impedance to a current flowing from one rail to the other.

"The track section A-Q is provided with asource of track circuit current which as here shown comprises the secondary winding 3 of a track transformer T which winding is constantly connected across the rails adjacent the exit end of the section. Interserial No. 603,952.

posed "betweenthe'lower rail of the section and one terminal of the secondary winding 3 is an impedance 5 one object of which is to limit the output of the transformer when the section is occupied by a train. The primarywinding 40f the transformer T is constantly supplied with alternatin' signalin-g current by meansof line wires?) fed from a generator G5 Section, A-B is also provided with a track relay R having two stator windings 6 and 7 and a rotor element 8 operatingia'conta'ct '9-1O. One of the stator windings 7 of this relay is constantly supplied with alternating current by wires 30 and 31 fro'm'line wires C, while the other winding 6 .is supplied with current from the track rails-of section i i- B as hereinafter explained. Section 'AB is also provided with-'a'sign'al 11 having a semaphore arm biased bygravity to such a position that it will display a stop indication, and also provided with operating mechanism for moving "the arm against this biasing force to such a position-that it will display a proceed indication. This mechanism is not essential to the complete disclosure of our present invention and has been omitted i'romthe drawing for the sake of simplicity. Itis sufiicient to say that the signal is provided with a'circuit which includesa source of energy. and the contact 910 on relay B. This circuit is closed only when contact 9-.10*on relay R is closed 'in which case the 'signal displays a'proceed indication.

Interposed between the lower track rail 2 and the relay winding 6 is a thermal cutout "D. "This cut-out comprises a base plate 12 of some insulating material such as slate or bakelite. Mounted on one end of this base plate -is-an upstanding post 18 having a terminal'21. Pivotally connected to this post is a movable contact finger 20 provided with. an insulated joint 19' and a contact tip 15. Mounted also on the base plate but spaced from the post 18 and from each other are two stationary contacts 18 and 14 so disposed as totengage the contact tip 15. The contact finger 2-0 is normally supported by a wire 16 in such a position that con tact 1-5- 1 1 is closed. This wire 16 is oi such size and material as to increase considerably in length when its temperature inated raises its temperature and increases its length with the result that the finger 20 is allowed to swing downward to open the contact 15-14 and close the contact 15-13.

The winding 6 of relay R is .provided with a circuit which passes from the upper rail of the section A-B through wires 23 and 24, winding 6, wire 25, contact 15-14 of thermal cut-out D, wire 16 of cut-out D, and wire 26 to the lower track rail of section A-B. An auxiliary path is provided for the current from rail to rail, which path passes from upper rail 2 through wire 23, through a resistance 22, wire 27, contact 15-18 of cut-out D, wire 16, post 18, and wire 26 to lower rail 2. The contact points on the cut-out D are adjusted so that contact 15-13 closes just before contact 15-14 opens. Thus it is plain that the circuit through wire 16 of cut-out D is closed'for either of its contact positions 'but that when contact 15-13 is closed the circuit includes resistance 22 and omits winding 6 of relay R. The resistance 22 is so designed that the current which passes through it due to a maximum amount of unbalancing of the propulsion current in track rails will not damage either it or cut-out D.

The operation of the apparatus is as follows:

Under normal conditions, that is, when the propulsion current in the track rails is not sufiiciently unbalanced to damage the track winding 6 of relay R, contact 15-14 of the cut-out D is closed, so that winding 6 of relay R is connected across the track rails and this relay operates to control the signal 11 in the usual manner. If, however, the propulsion current in the two track rails 2 becomes sufficiently unbalanced to damage the track winding 6 of relay R, the increased current through conductor 16 of the cut-out D causes this. conductor to expand to a suflicient extent to open contact 14-15 and close contact 13-15, thereby cutting winding 6 out of the track circuit and placing resistance 22 across the track rails in series with conductor 16. It follows that the cutout D remains in reversed position until the normal condition of the propulsion current circuit is restored, whereupon the cutout D returns to its initial position so that winding 6 of relay R is again placed in the track circuit. Obviously, when track winding 6 of relay R is disconnected from the track circuit by the cutout D thisrelay is opened, so that signal 11 indicates stop.

Although we have herein shown and de-' scribed only one form and arrangement of railway trafiic controlling app-aratus embodying our invention, it is understood that various changes and modifications may be -made therein within the scope of the appended claims without departing from the spirit and scope of our invention.

Having thus described our invention, what we claim is 1. In combination, an electric railway at least one track rail of which is included in the circuit for the propulsion current, a track circuit forsaid railway including a relay normally connected with the track rails, and means included in said track circuit and responsive to a predetermined amount of current for disconnecting said relay from the track circuit and connecting an auxiliary conductor across the track rails.

2. In combination, an electric railway at least one track rail of which is included in the circuit for the propulsion current, a track circuit for said railway including a relay normally connected with the track rails, a normally closed contact arranged when open to disconnect said relay from the track circuit, a normally open contact arranged when closed to close an auxiliary connection across the track rails, and means included in said track circuit and operating in response to a given amount of current to open the normally closed contact and close the normally open contact.

3. In combination, an electric railway at least one track rail of which is included in the circuit for the p-ropulsion current, a track circuit for said railway including a relay normally connected with the track rails, a normally closed contact arranged when open to disconnect said relay from the track circuit, a normally open contact arranged when closed to close an auxiliary connection across the track rails, and a conductor included in circuit with said relay and responsive to variations in current strength 'by comparatively great variations in length and operating when supplied with a given amount of current to opensaid normally closed contact and close said nor mally open contact.

4. in combination, an electric railway at least one track rail of which is included in the circuit for the propulsion current, a track circuit for said railway including a relay normally connected with thetrack rails, a conductor included in circuit with said relay and responsive to variations in current strength by comparatively great variations in length and means responsive to a given increase in the length of said conductor for disconnecting said relay from the track circuit and closing an auxiliary connection across the track rails in place of the relay.

5. In combination, an electric railway at least one track rail of which is included in the circuit for the propulsion current, a track circuit for said railway including a relay normally connected with the track rails, a normally closed contact arranged when open to disconnect said relay from the track circuit, a normally open contact arranged when closed to close an auxiliary connection across the track rails, and a conductor included in circuit with said relay and responsive to variations in current strength by comparatively great variations in length for controlling said contacts.

6. In combination, an electric railway at least one track rail of which is included in the circuit for the propulsion current, a track circuit for said railway including a relay normally connected with the track rails, a conductor included in said track circuit, and means controlled by the expansion of said conductor for disconnecting said relay from the track circuit and closing an auxiliary connection across the track rails.

T. In combination, a railway track, a track circuit for said track including a relay normally connected with the track rails, and means included in said track circuit and responsive to a predetermined amount of current for disconnecting said relay from the track circuit and connecting an auxiliary conductor across the track rails.

8. In combination, a railway track, a track circuit for said track including a re lay normally connected with the track rails, a normally closed contact arranged when open to disconnect said relay from the track circuit, a normally open contact arranged when closed to close an auxiliary connection across the track rails, and means included in said track circuit and operating in response to a given amount of current to open the normally closed contact and close the normally open contact.

9. In combination, a railway track, a track circuit for said track including a relay normally connected with the track rails, a normally closed contact arranged when open to disconnect said relay from the track circuit, a normally open contact arranged when closed to close an auxiliary connection across the track rails, and a conductor included in circuit with said relay and responsive to variations in current strength by comparatively great variations in length and operating when supplied with a given amount of current to open said normally closed contact and close said normally open contact.

10. In combination, an electric railway at least one track rail of which is included in the circuit for the propulsion current, a track circuit for said railway including a relay normally connected with the track rails, a conductor included in said track circuit, and means controlled by the expansion of said conductor for disconnecting said relay from the track circuit and closing an auxiliary connection through said conductor across said track rails.

11. In combination, a railway track, a normally closed contact and a normally open contact, a conductor responsive to variations in current strength by comparatively great variations in length and operating when supplied with a given amount of current to open said normally closed contact and close said normally open contact, a path across the rails of said track including said conductor and said normally closed contact and a track relay, and an auxiliary path across said track rails including said conductor and said normally open contact but not said track relay.

12. In combination, a railway track, a track circuit for said track including a track relay normally connected with the track rails, and means comprising a current responsive element included in said track circuit and responsive to a predetermined amount of current for disconnecting said relay froin the track circuit and connecting an auxiliary conductor including said current responsive element across the track rails.

In testimony whereof we afiix our signatures.

CHARLES R. BEALL. ROBERT M. GILSON. 

